abilitiesKoujaku is shown as being a competent, strong fighter. He could easily fall into the badass normal trope. He does have some extra abilities, though. In the game, it alludes to the tattoos granting him powers and extra strength. Once the tattoos take over him, he 1) can be controlled by Ryuuhou 2) turns into this. The tattoos seem to have a life of their own, too and can change colors and grow. In the band end, this is shown to be depicted like this. It seems if he gets very, very angry the tattoos can take over his mind and cause him to turn into his "other" form. This isn't seen until his route until the very end, so it's not a common occurrence where he randomly just hulks out. He also knows how to use his sword well, as he's seen carrying it around most of the time.

weapon (exsilium only!!)koujaku's weapon is a sword he has in canon. Here the sword takes on a slightly different form depending on Koujaku's mood/emotions. When he's calm and collected, the sword becomes indestructible, able to cut through almost anything. When he's worried, sad, or anxious, the sword is surrounded by ice, and whatever the blade touches, is encased in ice. Holding the sword too long in this state can cause frosting on his palms. When Koujaku feels angry or has lost control of his emotions, the sword is engulfed in fire and is extremely hot to the touch. Prolonged handling of the sword in this state can leave him with blisters and burns on his hands. Lastly, when he's extremely happy or he feels in love, the sword has a healing ability that can heal physical wounds and ailments (cuts, bruises, headaches, etc. not like regrowing limbs or curing a terminal/chronic illnesses). Currently he can only unlock its first form.